Updated on February 24, 2014
Prudent Parasite Prevention
Did you read about recent worries pertaining to a popular flea/heartworm/intestinal parasite prevention product called Trifexis? Some folks in the Atlanta area felt certain that this product caused the deaths of their dogs. Although autopsy examinations did not implicate Trifexis as the cause, such stories can create significant stress and anxiety for people, particularly for those already experiencing stress and anxiety about giving so many medications to their dogs for parasite control. Is all this recommended prevention truly necessary?
Below, I have provided you with my feelings about parasite prevention. Please keep in mind that the following thoughts represent simply one veterinarian’s opinion. This information should not replace discussion and decision-making with your own vet. Your choices should be based on your pet’s potential exposure to various parasites as well as your own personal preferences.
It used to be that I could tell you that if your dog lived in a particular state, city, or community you could skip heartworm prevention for your pets. Not so anymore. Heartworm disease now exists in every state within the United States. While it is intuitive to believe that a thick, long coat or exclusively indoor lifestyle will protect an animal from heartworm disease, this is not the case. Wherever an animal lives and whatever the plushness of their hair coat, year-round heartworm prevention is a good idea.
Here’s the good news about heartworm preventive medications. With rare exception, they are exceptionally safe. Adverse side effects are few and far between. Now, the bad news- heartworm resistance to commonly used preventive drugs has become a real phenomenon, documented most clearly in dogs living in the Mississippi Delta. The American Heartworm Society is currently funding research to learn more about heartworm resistance. For this reason, it is important to have dogs tested annually for heartworm disease even when heartworm preventive is being conscientiously administered.
Heartworms can cause serious damage and treatment of this disease is no walk in the park. I strongly recommend year-round heartworm preventive medication for your dogs and cats. The main exception to this recommendation applies to very elderly or infirmed pets who are not expected to live more than six months or so. This is the approximate amount of time it takes for significant symptoms to arise following heartworm infection.
FYI- my pets receive heartworm prevention once a month year round. I reside in the mountains of western North Carolina where the temperature drops below freezing during the winter.
Prevention of intestinal parasites (worms)
Dogs and cats are most likely to have intestinal parasites when they are puppies and kittens. This is because dormant stages of some intestinal worms are activated in the pregnant dog or cat and then “shared” with their offspring. Geography and lifestyle tend to dictate whether adult animals harbor intestinal parasites. For example, a dog living in North Carolina who frequents a busy dog park is far more likely to have intestinal worms than a Wyoming dog who never sets paw where other dogs tread.
Talk with your veterinarian to determine if intestinal parasite prevention is truly needed. Simply checking a stool sample for parasite eggs (this test is referred to as a fecal flotation) once or twice a year may be the way to go. Such testing is inexpensive and efficient. Worst-case scenario and your pet develops intestinal parasites- know that the treatment for this issue is safe, effective, and relatively inexpensive. If you are looking to thin out your pet’s menu of preventive medications, this would be a good one to consider dropping.
FYI- my pets do not receive intestinal parasite prevention. Rather, I run a fecal flotation once or twice a year to assess whether or not worms are present.
Flea prevention falls on the “optional” list in terms of parasite prevention. Some environments simply don’t propagate much in the way of fleas. For example, a strictly indoor kitty may remain flea-free. Fleas don’t thrive at high altitude, so flea prevention medications would be unnecessary in mile-high Denver, Colorado. Additionally, for some pets and their humans, living with a few fleas simply isn’t much of a nuisance. For your situation, use of flea prevention medication only during the “flea season” may work well. Or, it may be that year-round administration is required. Here’s the bottom line. Assess your pet’s environment and tolerance for fleas. A few flea bites may be the lesser of two evils when contemplating fleas versus flea prevention.
FYI- my pets receive monthly flea prevention during our “flea season”. They do not receive flea prevention during the winter months.
The incidence of tick-borne diseases is on the rise throughout much of the United States. Of all of these diseases, Lyme seems to get the most attention, perhaps because this disease is so common in people. Other significant tick-borne diseases include Rocky Mountain Spotted Fever, Ehrlichia, Anaplasma, and Bartonella. The incidence of these diseases varies widely from region to region within the United States. These infectious organisms can cause significant symptoms that may be life threatening. Additionally, in some cases they can be difficult to diagnose and/or treat effectively. The way to prevent these diseases is via effective tick prevention. This can take the form of avoidance of tick habitats during the tick season, “tick collars”, preventive medications, and/or careful tick surveillance (literally going over your pet with a fine tooth comb at least once a day).
To determine the best course of tick prevention in your household I recommend the following two things. First, determine if your pet has tick exposure. Have you ever seen one on your pet? Secondly, talk with your veterinarian about the incidence of tick-borne diseases in your community.
FYI- my pets receive monthly tick prevention medication, but only during the “tick season”.
Here are some important take home messages to help you create a prudent parasite prevention program for your pets:
- Year-round heartworm preventive medication is important regardless of where you live.
- Not all pets require year-round medications to prevent ticks, fleas, and intestinal parasites. For some animals, they may be important only during certain times of the year. For others, they are not needed at all.
- Double check that the prevention product you are using contains only the medications your pet truly needs. Avoid giving unnecessary medications simply because this happens to be the product on your veterinarian’s pharmacy shelf.
- Any parasite prevention medication is capable of producing an adverse or idiosyncratic response in any particular animal. If your pet develops symptoms on the heels of administrating such a product, contact your family veterinarian right away.
What parasite prevention products do you use?
Nancy Kay, DVM
Diplomate, American College of Veterinary Internal Medicine
Author of Speaking for Spot: Be the Advocate Your Dog Needs to Live a Happy, Healthy, Longer Life
Author of Your Dog’s Best Health: A Dozen Reasonable Things to Expect From Your Vet
Recipient, Leo K. Bustad Companion Animal Veterinarian of the Year Award
Recipient, American Animal Hospital Association Animal Welfare and Humane Ethics Award
Recipient, Dog Writers Association of America Award for Best Blog
Recipient, Eukanuba Canine Health Award
Recipient, AKC Club Publication Excellence Award
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Please visit http://www.speakingforspot.com to read excerpts from Speaking for Spot and Your Dog’s Best Health. There you will also find “Advocacy Aids”- helpful health forms you can download and use for your own dog, and a collection of published articles on advocating for your pet’s health. Speaking for Spot and Your Dog’s Best Health are available at www.speakingforspot.com, Amazon.com, local bookstores, and your favorite online book seller.